Differential electric distant control device comprising static



Feb. 12, 1929. V 1,701,671

E. GRANAT DIFFERENTIAL ELECTRIC DISTANT-CDNTROL DEVICE COMPRISING STATICTRANSI ITTBRS Filed Aug. 1926 3 Sheets-Sheet 1 Feb. 12, 1929. r1,701,671 E. GRANAT DIFFERENTIAL ELECTRIC DISTANT CONTROL DEVICEGOIPRISING STATIC TRANSIITTERS Filed Aug. ,1926 3 Sheets-Sheet 2 v Feb.12, 1929. 1,701,671

--E. GRANAT' DIFFERENTIAL ELECTRIC DISTQNT CQIITRQL DEVICE COMPRISINGSTATIC TRANSIITTERS Filed Aug. 5, 1926 3 Sheets-Sheet 3 17 1 60/01Zfranaf M MM Patented Feb. 12, 1929.

UNITED STATES PATENT OFFICE.

ELIE GRANAT, 0] IARIS, FBAN CE, ASSIGNOR OF ONE-HALF TO COIPAG'NIE DESmuons ET ACIEBIES DE LA MARINE ET DHOMECOURT, 0F PARIS, IRAN CE, A COI-PANY OF FRANCE.

DIFFERENTIAL ELECTRIC DISTANT CONTROL DEVICE COMPRISING STATICTRANSMITTEBS.

Application filed August 8, 1926, Serial No. 126,838, and in FranceOctober 5, 1985.

I have already described difierential electric distant control devicescomprising transmitters constituted by electric machines, either motorsor generators fed either with direct or polyphase current and providedwith a commutator against which rub two or more sets of movable brushescontrolled each by a corresponding control device, the movements ofrotation of which are to be added algebraically. These sets of brushesare connected one with the feedin line and the remainder with thetransmission line or lines.

A difi'erential distant control device of this type adapted to be fedwith direct current is described in my patent application Ser. No.21,175 (Fig. 1) filed on Sept. 14, 1925, and the title of which isElectric diflt'erential control system.

Another control device adapted to be fed with alternating or polyphasecurrent is described in my patent application Ser. No. 56,380, filed onSept. 14, 1925, and the title of which is Polyphase distant controlsystem for clifierential transmission.

In some cases the use of transmitters constituted by electric machines,either motors or generators, can because they require these dynamicmachines, prove disadvanta eous and show one or more of the followingdrawbacks:

Bulkiness,

Difficulty of machining and mounting,

Up-keep and lubrication of the rotating parts,

Heat developed in some parts b friction.

My invention described herein elow has for its object to do away withthese drawbacks. It consists chiefly in using as a transmitter for thedifferential electric distant control device a device comprisingstationary windings.

These static transmitters can be of different types. Some can be fedwith direct current and others with one-phase or polyphase alternatingcurrent. They comprise one or more commutators on which rub on one handa set of movable feeding brushes controlled by one of the parts themovement of which is to be transmitted and on the other hand one or moresets of brushes connected with the transmission line and controlled bythe part or parts the movement of which is to be added algebraically tothe movement of the first part mentioned hereinabove.

A'drawback of distant control devices comprisin static transmitters liesin the fact that t ey do not allow the controlled part to be moved in acontinuous manner, it can only be moved in a discontinuous manner andcocupy in succession a given number of redetermined positions. Thereason of t is is that the movable brushes of the transmitter which areconnected with the transmission wires move over a stationary commutatorand that therefore the number of ositions of the movable brush setcorrespon ing to different electric combinations liable to give themovable part of the receiver a different position is limited.

My invention comprises also means for avoiding this drawback byasuitable choice of the number of commutator segments as compared withthe number of movable brushes connected with the line wires.

will be disclosed with more detail hereinafter.

The invention comprises, further, devices allowing the position of thefinal receiving part of the transmission to be corrected at thereceiving station.

Lastly the invention discloses an arrangement which shows the greatadvantage of requiring in the diiferent control stations simple ordifferential transmitters either dy-- namic or static, of only smalloutput whereby their bulkiness is much reduced. This is provided by thefact that these transmitters control only the rotation of a synchronousreceiving motor actuating a set of movable brushes rubbin on thecommutator of a transmitter having a high output.

The connecting wires starting from these brushes feed in their turn oneor more synchronoiis receivers of high output. I obtain in this manner apower amplifying device causing no delay.

By way of example I have described hereinbelow and shown on appendeddrawin several forms of execution of difierentia electric distantcontrol devices comprising a static transmitter.

In order to be readily understood I have described first with referenceto the appended drawings the previous arrangements in-- vented by me andworking with dynamic transmitters.

Figs. 1 and 2 show respectively two dynamic transmitters fordifferential distant control devices adapted to be fed, the first withdirect current, the second with three phasecurrent.

Fig. 3 shows a differential distant control device working with a statictransmitter and adapted to be fed with direct current or with one-phasealternating current.

Fig. 4 shows an arrangement for use with the receiver of thedifierential control device shown on Fig. 3 whereby a correction can bemade at the receiving station to the position of the final receivingpart of the transmission.

Fig. 5 shows a diflerential control device working with a statictransmitter and adapted to be fed with three phase current.

Fig. 6 is a modified form of the transmitter of a differential controldevice of the'type shown in Fig. 5.

Fig. 7 shows an arrangement for use with the receiver of thedifferential distant-control device shown in Fig. 5 whereby the positionof the final receiving part of the transmission can be corrected at thereceiving station.

Fig. 8 shows a modified form of the receiver of the differential distantcontrol devices shown in Figs. 3 and 5.

Fig. 9 shows a device providing for a differential distant electriccontrol and yielding at the receiver a great power though it requiresfor the transmission only static or dynamic transmitters having a smalloutput.

According to Fig. 1 the dynamic transmitters of the differential distantcontrol device adapted to be fed witlrD. C. and described in my patentapplication 21,175 has been diagrammatically drawn in the followingmanner: An electric dynamo machine, either a. motor or a generatorcomprises a distributed inducing stator 1 and a rotor 2 provided with acommutator 3. Two brushes 4-5 can rub on this commutator and feed thearmature with direct current supplied through the line wires 6-7. Thesetwo feedin brushes 4 and 5 are borne b a movable hdlder 8 the movementof which is obtained through the handwheel 8. These said feeding brushesare connected with the feeding wires 6 .and 7 through an arrangement,not shown on the diagrammatical sketch of rings and of sliding contactsof the usual type.

On the commutator 3 of the armature of the dynamo-electric machine rubalso three stationary equidistant brushes 9-10-11 connected with threeequidistant points of the winding of the stator 1. On this samecommutator 3 rub also three movable brushes 12-13-14 respectivelyconnected'through rings and sliding contacts not shown with threetransmission wires 15-16- 17 connecting the transmitter with thereceiver. These brushes are mounted on a movable holder 18 controlled bya handwheel 19.

I have explained in my previous patent application 21,175 that themovement of the rotor of the receiver (which is the same as that shownin the transmission illustrated by appended Fig. 3) gave the algebraicalsum of the rotations of the movable feeding brushes 4-5 controlled bythe handwheel 8' and 01" the movable brushes 12-13-14 controlled by thehandwheel 19 and connected with the transmission line.

The transmitter shown diagrammatically on Fig. 2 and which is the sameas the one described in my previous patent application Ser. No. 56,380,dated September 14, 1925, and illustrated on Fig. 4 of this saidapplication comprises the following parts constituting a dynamo-electricmachine, either a' motor or a generator.

A field stator 20 provided with three equidistant terminals 21-22-23connected with the wires 24-25-26 of a three phase feeding line.

A rotor 27 the sections of which are connected with the segments of thecommutator 28. On this commutatorrub three sets of brushes.

1. A group of three stationary brushes 29,

30, 31 connected with the terminals 23 of the stator.

2. A group of three movable brushes 32-33-34 also connected by means ofrings and sliding contacts not shown with the same current terminals 21,22, 23 of the stator; these three movable brushes 32, 33, 34 are borneby a movable holder 35 controlled by a handwheel 36.

3. A group of three movable brushes 37-38-39 borne by a movable holder40 controlled by a handwheel 41. These three last movable contacts 37,38, 39 are connected through rings and sliding contacts not shown withthe three transmission wires 42, 42, 42

connecting the transmitter with the receiver.

As explained in my previous aforemen-.

tioned patent application, the rotationsof the movable part of thereceiver are .in this device the sum of the rotations of the movablefeed brushes 32, 33, 34 controlled by the hand wheel 36 and of themovable brushes 37 38, 39 connected with the transmission wires andcontrolled by the handwheel 41.

After having recalled the dynamic ar- On this commutator rub on one handtwo feed brushes 53, 54 connected by rings and sliding contacts notshown to a direct or onephase feeding line 5556 and borne by a movableholder 57 controlled by the hand wheel 58.

On the other hand the three movable brushes 59, 60, 61 connected throughrings and sliding contacts not shown with the three transmission wires62, 63, 64; are borne by a movable holder 65 controlled by the handwheel66.

The receiver is constituted by a so-called auto-synchronous motorcomprising a field stator 67 fed by means of direct or one-phase linewires 68-69 and a three-phase rotor 7 0 connected through rings andsliding contacts not shown with the three transmission wires 62, 63, 64.The working of this device is the followlng:

If the holder of the movable brushes 59, 60, 61 connected with thetransmission wires remains stationary and if the two feed brushes 53, 54are moved by means of the handwheel 58 the distribution of thepotentials under the three brushes 59, 60, 61 is shifted by acorresponding amount, and thereby the resulting field of the armature 70of the receiving motor is rotated. This motor is thus controlled by'therotation of the two feeding brushes 5354: controlled by the handwheel58. i

If on the other hand the feeding brushes 5354= remain stationary and theset of three movable brushes 59, 60, 61 connected with the transmissionwires is moved, the phase of the potential under these brushes ismodified whereby the resulting field of the armature of the receiver iscaused to rotate by a corresponding amount equal to the rotation of thethree movable brushes 59-6061.

In the differential control device shown on Fig. 5, the transmitter is astatic machine devised as follows: A winding connected as anauto-transformer 71 has its ditlerent sections connected with thesegments of the commutator 72. This winding is wound on a magnetic corediagrammatically shown at 73.

On this commutator rub two sets of movable brushes: on one hand threefeeding brushes 74, 75, 76 borne by a movable holder 77 controlled by ahandwheel 78 and connect-,

ed with the three line wires 79, 80, 81 of a three-phase feeding line;on the other hand three transmission brushes 82, 83, 84 mounted on amovable holder 85 controlled by a handwheel 86 and connected with thethree line wires 87 88, 89 connected with the receiver.

The receiver is constituted by a motor with a double winding comprisinga three-phase stator 90 the three equidistant terminals 91, 92, 93 ofwhich are fed through the three wires 94, 95, 96 of the same three-phasetrans mission which feeds the transmitter and a three-phase rotor 97connected throu h rings and sliding contacts not shown with t e threeline wires 878889.

The working of the device is the followsponding rotation of the rotor ofthe receiver.

Fig. 6 shows a modified form of the transmitter shown on Fig. 5. In thismodified form, the auto-transformer winding 71 is replaced by atransformer having two independent windings, primar and secondary,acting one on the other. y means of this latter arrangement the feedingvoltage of the controlled electric transmission can be raised orlowered, this proving advantageous in certain cases. I

The transformer comprises a primary winding 101 the sections of whichare connected with the segments of the commutator 102 and a secondarywinding 103 the sections of which are connected with the segments of thecommutator 10 1.

On the collector 102 of the primary winding rub three movableequidistant brushes 105 106107 borne by a holder 108 controlled by ahandwheel 109 and connected with the three phase feeding wires 110, 111,112.

On the collector 104 of the secondary winding 103 rub'three movablebrushes 113, 114, 115 borne by a holder 116 controlled-by a handwheel117 and connected with the three transmission wires 118119120. Thesetransmission wires are connected with the rotor of a motor of the typeillustrated by Fig. 5.

The working of the arrangement is the same as in Fig. 5; according tothe diagrams shownon Figs. 4 and 7 the receivers of the differentialcontrol device, shown on Fig. 3 and on Figs. 5 or 6 can be arranged soas to allow the position of the rotor of the receiver to be directlycorrected at the receiver itself.

Accordingto the diagram shown on Fig. 4 and corresponding to the controldevice illustrated by Fig. 3, the receiver is constituted by a fieldstator provided with a distributed winding 121 the sections of which areconnected with the commutator 122. On

.this commutator rub two movable brushes 123, 124 connected by rings andsliding contacts not shown, with two direct or one-phase line wires 125,126. These two brushes are mounted on a movable holder127 controlled bya handwheel 128. The three-phase rotor does not show any modificationsover that previously described and is constituted by a winding 70 fed bythe three transmission Wires 626364.

By makin the set of brushes 123, 124 rotate, the resu ting field of thefieldstator will move by a corresponding angle and thereby thethree-phase rotor of the receiver will rotate by the same angle., Thusit is possible to add algebraically to the transmitted rotations acorrection at the receiver itself.

In the receiver shown on Fig. 7 which is a modification of that of Fig.for a. diiferential control arrangement fed with threephase current, thefield stator 130 is a distributed winding the'sections of which areconnected with a commutator 131. The rotor is the usual three-phaserotor 97 connected by means of rings and sliding contacts with the threewires of-the transmission 87, 88, 89.

On the commutator 131 of the field piece 'rub three brushes 132, 133,134 connected respectively with the three wires 94, 95, 96 of the threephase feeding line which also feeds the transmitter.

By rotating the movable set of brushes 132 133-134, the phase of thevoltage feeding the field stator-can be varied whereby a correspondingrotation of the rotor of the receiver is obtained. a

Fig. 8 shows a receiving motor provided with a double polyphase windingboth parts of which are fed by a shunt taken from the transmissionwires. The stator 135, the rotor 136 are both fed by three wires of thedistant control arrangement,137-138- 139 by means of shunt connectionsbetween the three terminals 140141'14 2 of the stator and the threeterminals 143-144-14:5 of the rotor winding. The working of this deviceis the following:

If the two windings 135-136 have the same number of poles theconnections are disposed so that the fields arising in the rotor and inthe stator rotate in opposite directions whereby their angular relativedisplacement for any movement'of one of the controlling devices isdouble the absolute rotation of each field taken per se. Under theseconditions any movement of one of the controlling devices of thetransmitter'will cause a rotation of the rotor 136 by double the amount.

If the said windings do not have the same number of poles theconnections will be made so that the two fields, that of the stator andthat of the rotor rotate in the same direction. Each rotation of one ofthe controlling devices of the transmitter will have for its effect toprovide a corresponding rotation of the rotor 136 of the receiver whichis ina given ratio with that of the'said controlling device. I

If for instance the winding of the stator comprises 2 poles and that ofthe rotor 2 (p1) p0 es: for a rotation at of one of the sets of themovable brushes of the transmitter, the field of the stator will rotateby g and that of the rotor by a a a the rotor will rotate by p 1 p Thisdevice shows thus the advantage of providing an electric Vernier.

The use of such a receiver shows great advantages in the case where thecurrent feeding the transmitter cannot be used for feeding the receiver.

A drawback of static transmitters for distant control arrangementsresides in the fact that the, number of positions of the receiver islimited, as explained hereinbefore. I will now show it is possible by aproper choice of the number of brushes of the transmitter connected withthe transmission wires as compared with the number of segments of thecommutator on which these brushes rub, to obtain a great number ofpositions forthe receiver, which practice amounts to having theadvantages provided by distant control devices with, dynamictransmitters allowing a continuous movement.

I have discovered the following formulae.

Suppose a is the number of brushes of the transmitter connected with thetransmission line, n the number of segments of the commutator on whichrub these brushes, ;0 the number of positions which the rotor of thereceiver can take:

1. If n is a multiple of a, p is equal tort or otherwise stated, thenumber of positions is equal to the number of segments of thecommutator,

2. If n is not an exact multiple of a the number of positions is givenby the formula p=2 nXa. Suppose d is the greatest common divisor betweena and n: we have:

If n is a multiple of a, p is equal to n or otherwise the number ofpositions is equal to the number of the segments of the commutator.

If 'n, is not a multiple of a, the number of 21141 the positions 1sgiven by p= If there is between n and a no common divisor, but unit,then d =1 and the number of'positions is given by the formula p=2na.

The table given hereunder shows for a three-wire transmission the numberof positions p corresponding to the number of seg ments 1?. of thecommutator. It can be seen by this table that the cases where n is amultiple of a are particularly disadvantageous and that on the contrarythe other cases give values of p which increase with the number ofsegments. The number of segments will therefore according to the presentinvention Thus be chosen so as to correspond to the number and areceiver one component of which is fed of positions which is desired totransmit.

In the case where the power transmitted by a distant control arrangementis to be amplified, that is if the small power distant controlarrangement is to be followed by a high power distant controlarrangement it is of particular advantage, for obtaining a nondelayedpower amplifying transmission, to use the receiving motor of one of thesmall power distant control arrangements described hereinabove. Forcontrolling the rotation of a set of movable brushes of a transmitterconstituted by a high power machine (motor or generator) the receiver ofwhich controls the part to be actuated.

According to the diagram shown on Fig. 9 the receiver of the distantcontrol device, illustrated on the left hand side, is constituted likethe one shown on Fig. 3 by a field stator 6'? which is fed with director onephase current and by a three-phase rotor fed by the three wires62, 63, 6 1 of the transmission. The shaft 150 of the rotor bears themovable set of three equidistant brushes 151, 152, 153 rubbing on thecommutator 15 1 of the transmitting motor 155 fed with one phase ordirect current through the brushes l56157. The three movable brushes151* 152l53 are connected by three rings 158 with the three line wires159 connecting the motor 155 with one of the receivers it controls.

T he working is the following:

All the controlling operations made at the transmitter of the firststatic small power distant control arrangement are added on the rotor 70of its receiver; all the movements of this rotor 70 are transmitted tothe three brushes 151152153 of the transmitter 155 which transmits themto the several receivers it controls.

What I claim is:

1. A difl'erential electric distant control arrangement comprising atransmitter constituted by a stationary winding, means whereby thiswinding is fed from the mains throu h equidistant points, means forcontrolling t e position of these points on the said winding,

' wires through which energy is removed from said winding, means forcontrolling the phase of this energy with reference to the windingdirectly by the said wires and the other is fed with current, thedifference in phase of which with reference to the first com onent is afunction of that of the energy fe from the transmitter with reference tothe mains. 2. A differential electric distant control arrangementcomprising a transmitter constituted by a stationary winding, astationary energy is removed from said winding, wires connected withsaid brushes, a handwheel adapted to control the angular position of thelast mentioned brushes with reference to the first set, a receiver onecomponent of which is fed directly by the said last mentioned wires andthe other is fed with current the difference in phase of which withreference to the first component is a function of that of the energy fedfrom the transmitter with reference to the mains.

3. A dilferential electric distant control arrangement comprising atransmitter constituted by two stationary interacting windings, twocommutators connected respectively with each winding, two sets ofmovable brushes adapted to rub respectively on each commutator, meansfor controlling the position of each set of brushes with reference toits commutator, a receiver, wires connectin respectively one set ofbrushes with the A. mains and the other with one component of thereceiver and means for feedin the smond component of the receiver witcurrent the phase displacement of which with that "feeding the firstcomponent is in a simple ratio with that of the last mentioned currentwith reference to the mains.

a. A differential electric distant control arrangement comprising atransmitter constituted by a stationary winding, a stationary commutatorof n segments connected therewith, a set of a movable brushes adapted torub on said commutator and connected with the mains n and (1 having avery small common divisor, a handwheel controlling said movable brushes,another set of movable brushes through which energy is removed from saidwinding, wires connected with said brushes, a handwheel adapted tocontrol the angular osition of the last mentioned brushes with re erenceto the first set, a receiver one component of which is fed directly bythe said last mentioned wires and the other is fed with current thediiference in phase of which with reference to the first component is afunction of that of the energy fed from the transmitter with referenceto the mains.

5. A differential electric distant control arrangement comprising atransmitter constituted by a stationary winding, means wh another set ofmovable brushes through which connections with the two components beingmade in o posite manner.

6. A di erential electric distant control arrangement comprising atranmitter constituted by a stationary winding, means whereby thiswinding is fed from the mains through equidistant points, means forcontrolling the position of these points on the said winding, wiresthrough which energy is removed from said winding, means for controllingthe phase of this energy with reference to that in the winding, areceiver, a set of, movable brushes fed directly by said wires andadapted to feed one component of said receiver, a handwheel controllingsaid brushes and means whereby the other component of the receiver isfed with current the phase displacement of which with reference to thefirst component is in a simple ratio with that of the latter withreference to the mains.

7 A differential electric distant control system comprising in seriesstatic control arrangements as claimed in claim 1 and dynamic controldevices, the rotor of the re- .ceiver of each arrangement and devicecontrolhng the controlling part of the following transmitter.

In testimony whereof I aflix my signature.

ELIE GRAN AT.

